What are glue records?
Learn what glue records are, when they matter, and why they are important for in-bailiwick nameservers.
What glue records are
Glue records are address records published at the parent side to help resolvers find in-bailiwick authoritative nameservers.
They are needed when a nameserver lives inside the same zone or delegation chain that it serves.
Why glue is needed
Without usable address information, a resolver can face a circular problem: it needs the nameserver to resolve the zone, but it also needs the zone to resolve the nameserver.
Glue helps break that dependency.
Simple example
Suppose example.com uses ns1.example.com as an authoritative nameserver. A resolver may need address information for ns1.example.com before it can successfully use that nameserver for the domain.
That is the kind of scenario where glue becomes important.
What to check
- Whether the nameserver is in-bailiwick
- Whether it has usable A or AAAA records
- Whether the delegation design still makes sense after changes
Common glue-related problems
- Missing address records for in-bailiwick nameservers
- Old registrar-side expectations after delegation changes
- Confusion between ordinary resolution and parent-side delegation requirements